Various electronic control systems are used in automotive vehicles. In order to decrease the length of connecting lines, it is desirable to place the control systems near the engine, and particularly under the hood of the engine compartment of an automotive vehicle, mounted preferably against a metal component of the vehicle or against the chassis, so that the housing can additionally function as a heat conductor to carry away heat generated within components of the control system which should be cooled.
Control systems, as heretofore, proposed usually were enclosed in metallic shells or housing structures. To secure a printed circuit board into the housing, as well as components forming plug-and-socket connections, screws, rivets or the like were usually used which, in order to provide insulation, required additional insulating washers, bushings, or the like. Assembling additional insulators into the housing increases both the costs of materials for the overall system, as well as assembly costs. The printed circuit board itself must be laid out such that sufficient space is provided for insulating regions thereon. Consequently, the printed circuit board cannot be miniaturized and made as small as consistent with the electrical network placed thereon, since additional structural space capable of absorbing stresses, vibration and shock encountered in automotive use has to be provided, while still permitting attachment of the printed circuit board, in insulated relation with respect to the metallic housing structure. Thus, the overall size of the unit is larger than that determined solely by the electrical characteristics of the components placed within the housing structure.